1. Field of the Invention
This invention relates to a device for automatically mounting web rolls, each having a core and a belt-like thin sheet or a web wound therearound, used in an apparatus for taking off the web from each of the web rolls, and more particularly to a web changing device for automatically replacing, with a new web roll, the used web roll mounted in a web supplying apparatus for continuously taking off webs from paper web rolls and supplying the webs to the web changing device. The web supplying apparatus is used in a machine for manufacturing cigarette rods, filter rods and the like, which are intermediate products of cigarettes.
2. Description of the Related Art
In the conventional cigarette manufacturing process, belt-like paper sheets are wound around cigarette material to form elongated cigarette rods, and thereafter the rods are cut into pieces each having a predetermined length. Similarly, when filters are manufactured in the conventional process, belt-like paper sheets are also wound around filter sheets made of fiber or the like to form elongated filter rods and thereafter the filter rods are cut into pieces each having a predetermined length.
Therefore, continuous supply of the above-mentioned belt-like paper pieces, i.e., webs, is required for producing cigarette rods and filter rods. Such a web is usually supplied in a form of the web roll comprising a core and a web wound around a roll, as shown in FIG. 7. The web roll is mounted in a web supplying apparatus and the web is continuously taken off from the web roll and is supplied therefrom to the succeeding apparatus. When the web on the web roll is fully used, a web is taken off from a new web roll and the leading end of the new web is connected to the trailing end of the web from the old web roll. In such a way, webs are supplied continuously.
There has been recently developed a web supplying device which is provided with two web rolls so as to perform these processes automatically. A web is taken off from a first web roll and is supplied to the succeeding apparatus. When the web on the first web roll is fully used, a web is drawn out from the second web roll which was in a waiting state, and the leading end of the web on the second web roll is automatically connected to the trailing end of the web of the first web roll. Thereafter, the core and other necessary parts are removed from the web supplying apparatus, and a new web roll is mounted thereon. With this web supplying device, this series of web supplying and web replacing processes is repeated so that webs are supplied continuously.
Since, however, cigarette manufacturing machines have been operated at a higher speed thereby increasing the amount of webs to be supplied, the web on a web roll is fully used in about ten minutes. In order to replace the used roll with the one new every ten minutes, an operator must be fully engaged in the replacement work of the web rolls.
It is very difficult for the operator to endure such a continuous simple task for a long time, and in addition thereto, the manpower cost increases.